Adjustable ozone delivery system for air disinfection

ABSTRACT

An UV light system ( 10 ) for treating the air includes an UV tube lamp ( 20 ) having a first section ( 42 ) for transmitting UV light in a wavelength range thaht includes maximum ozone production and maximum germicidal activity, and a second section ( 44 ) for transmitting UV light in a wavelength range thaht includes maximum germical activity while excluding the production of ozone; and a movable annualar sleeve ( 46 ) for controlling the amount of ozone transmitted by the lamp ( 20 ).

[0001] This application claims priority to U.S. Provisional PatentApplication Serial No. 60/260,565 filed Jan. 9, 2001.

TECHNICAL FIELD OF THE INVENTION

[0002] The present invention relates to an ultraviolet (hereinafter“UV”) light apparatus, module and system for the treatment of air which,upon exposure to UV light, will destroy harmful bacteria,micro-organisms and/or offensive and noxious odors in the air containedwithin a confined space or in air passing through a confined space suchas a conduit or a heating/ventilation air conditioning (hereinafter“HVAC”) duct.

BACKGROUND ART OF THE INVENTION

[0003] UV light sources for the treatment of air typically take the formof a UV lamp positioned within a confined space such as thecross-sectional area of a conduit, for example, in a HVAC duct locatedin the home or an office building. UV lamps, such as those disclosed inU.S. Pat. No. 5,751,007 issued May 12, 1998, are known to emit UV lightthrough two different types of tubing contained in the lamp, therebygenerating UV light at different radiation wavelengths for destroyingharmful bacteria and for the production of ozone to remove offensive andnoxious odors. According to the disclosure of this patent, one kind oftubing will transmit light at wavelengths over the full radiationspectrum of UV light (what the patent refers to as UVA and UVB light),and the other tubing will transmit light at wavelengths only above 200nanometers (defined in the patent as UVA light). The patent refers toUVA light as that light which is transmitted at wavelengths above 200nanometers, and UVB light as that light which is transmitted atradiation wavelengths below 200 nanometers. However, according to aMicrosoft Encarta Online Encyclopedia article entitled “UltravioletLight” by Thomas W. Davis, M.S., Ph.D. (published by the MicrosoftCorporation, 2000), UV light is often divided into three differentwavelength categories: UVA, UVB and UVC. In general, the shorterwavelengths of UV radiation are more dangerous to living organisms.Thus, UVA light has a wavelength from about 400 to about 315 nanometers;UVB light occurs at wavelengths from about 315 to about 280 nanometers,which causes sunburn and can cause skin cancer upon prolonged exposure;and UVC light has radiation wavelengths of approximately 290 to 15nanometers which is often used to sterilize surfaces because of itsgermicidal activity against bacteria, viruses and micro-organisms. The“Oxford Dictionary Of Science,” on the other hand, classifiesultraviolet light ranges according to its effects on the human skin, asUV-A (320-400 nm), UV-B (290-320), and UV-C (230-290 nm). And accordingto U.S. Pat. No. 4,967,090 issued Oct. 30, 1990, the U.S. FDA (Food andDrug Administration) defines UVA as the region of 320-400 nm and UVB asthe region of 260-320 nm. In view of the foregoing discrepancies, andfor the purposes of describing the invention herein, the term UVC shallrefer to that ultraviolet light which occurs in the range of from about15 to about 290 nanometers. Nonetheless, tubing consisting of specialformula glass may be designed to be transparent to the longer UVwavelengths, while the use of pure quartz tubing is transparent to theentire, naturally occurring range of UV light, including ultravioletranges below 200 nm.

[0004] Within the UVC range of ultraviolet light as defined above,maximum germicidal activity is recognized to occur at a radiationwavelength of about 253.7 nanometers. As indicated above, germicidalactivity alone (without the production of ozone) can be effected by theuse of specially prepared quartz tubing for the UV lamp that is commonlyreferred to in the industry as L-quartz, which is quartz doped withtitanium dioxide. However, when UVC light interacts with the oxygen inthe ambient atmosphere at a radiation wavelength of approximately 185nanometers, maximum ozone generation and output occurs. The productionof ozone at this wavelength helps to reduce or substantially eliminateoffensive and/or noxious odors that occur within the air, such as in airconditioning ducts in the home or office buildings when no fresh air isbeing introduced into the system. This condition generally occurs whenair is being constantly re-circulated through a HVAC system undercircumstances when minimal amounts of fresh air are introduced into thesystem, typically during cold weather conditions in order to conserveheat and reduce energy consumption.

[0005] As indicated above, ozone production from a UV lamp can beeffected by the use of high quality clear quartz tubing, available andreferred to in the industry as VH-quartz, which allows the transmissionof UV light at both the 185 and 253.7 nanometer radiation wavelengths.Therefore, by employing a UV lamp having both these types of tubing, incombination with an adjustable sleeve covering a portion of theVH-quartz tubing for blocking or absorbing the transmission ofultraviolet light that will produce ozone, such as that described inU.S. Pat. No. 5,751,007, one can purify and/or treat the air andsimultaneously control the production of ozone for eliminating offensiveand/or noxious odors.

[0006] Unfortunately, the control of the rate of ozone emitted in a HVACduct by a system that employs the UV lamp apparatus described in U.S.Pat. No. 5,751,007, is hampered by the duct system that conveys theconditioned air, either because of the inaccessibility of the UV lampitself, or because of the necessity of having to shut down the UV airdisinfection system to manually adjust the sleeve which, in this patent,is mounted directly to the lamp's tubing. It is therefore important anddesirable to monitor the levels of ozone and provide for the manualand/or automatic adjustment of the sleeve from a location exteriorand/or remote from the duct system, without having to shut down theoperation of the UV air disinfection system. Discontinuing operation ofthe system to either change the lamp or to manually adjust the sleeve'sposition for controlling the UV lamp's ozone output also leads to aninefficient operation. Furthermore, it should be kept in mind that whilethe formation of ozone within the duct is desirable for reducing and/oreliminating noxious odors, the ozone produced should not reach levelswhere it becomes toxic to the persons being exposed to it, sinceprolonged exposure to elevated levels of ozone can be harmful.

BRIEF DISCLOSURE OF THE INVENTION

[0007] In order to overcome the foregoing difficulties, the presentinvention provides an ultraviolet light apparatus, module and system forthe treatment of air within a confined structure, such as a HVAC duct,to disinfect the air therein, and for controlling the amount of ozonegenerated by the ultraviolet light apparatus for substantially reducingand/or eliminating offensive and/or noxious odors carried by the airwithin the confined structure.

[0008] The ultraviolet light apparatus comprises an ultravioletlight-emitting lamp that includes at least one composite tubing whichcomprises (a) a first section for transmitting ultraviolet light in awavelength range that includes maximum ozone production and maximumgermicidal activity; and (b) a second section for transmittingultraviolet light in a wavelength range that includes maximum germicidalactivity and excludes the production of ozone. The ultraviolet lightapparatus also includes (c) a movable annular sleeve whose annuluscompletely surrounds a portion of the composite tubing of theultraviolet light-emitting lamp in a frictionless manner. The sleeve iscapable of blocking ultraviolet light in a wavelength range thatproduces ozone while simultaneously allowing the transmission ofultraviolet light at a wavelength range that produces germicidalactivity.

[0009] The ultraviolet light-emitting lamp may be configured ascomprising a straight composite tubing, or it may comprise two,substantially parallel, tubularly connected segments, the first sectionof the composite tubing forming a portion of at least one of thesegments. This includes a UV lamp having a generally C-shapedconfiguration whose opposite ends terminate in a common lamp base.

[0010] The annular sleeve is such that it is capable of blockingultraviolet light in a wavelength range that produces ozone whilesimultaneously allowing the transmission of ultraviolet light in awavelength range that produces germicidal activity. In order toaccomplish this, the sleeve is preferably constructed of speciallyprepared fused quartz (known in the industry as “L-quartz”) ortransparent Teflon®. The annular sleeve is preferably of sufficientlength to completely surround the first section of the composite tubingof the ultraviolet light-emitting lamp.

[0011] Alternatively, the entire tubing of the ultravioletlight-emitting lamp may be such that it will transmit ultraviolet lightin a wavelength range that includes maximum ozone production and maximumgermicidal activity, and includes tubing that has a straight length aswell as two, substantially parallel, tubularly connected segments asdescribed above. In either case, the opening of the sleeve combined withthe sleeve's length, is configured such that it will completely surroundthe entire tubing of the ultraviolet light-emitting lamp. The annularsleeve has the same characteristics as the sleeve described above forthe UV lamp comprising the composite tubing.

[0012] The invention also extends to the utilization of the ultravioletlight apparatus in modular form for operation of the annular sleeve tocontrol the amount of ozone transmitted by the ultravioletlight-emitting apparatus to a confined space, e.g., a conduit having thepassage of air flowing therethrough. Therefore, in addition to theultraviolet light apparatus, the ultraviolet light module comprises adrive mechanism for the frictionless displacement of the annular sleevealong the longitudinal axis of the ultraviolet light apparatus'composite tubing for controlling the amount of ozone transmitted by thesame.

[0013] In one aspect of the invention, the drive mechanism comprises anelongate threaded rod engaged at one end portion thereof with a meansfor rotating the rod, preferably an electric motor, with the oppositeend portion of the rod being operatively engaged with a correspondinglythreaded opening within a retainer member mounted to or fixed to theannular sleeve. When the threaded rod is rotated by, for example, anelectric motor, or manually by the employment of a handle on the endportion of the threaded rod, the annular sleeve will be displaced alongthe longitudinal axis of the composite tubing of the ultravioletlight-emitting lamp. A guide rod may optionally be detachably fixed tothe conduit to which the module is incorporated with, such that theguide rod communicates with a slidable stabilizer member fixed to theretainer member, the guide rod being in parallel relationship with thethreaded rod to prevent the transmission of torsional forces to theannular sleeve by the rotation of the threaded rod.

[0014] Alternatively, and in keeping with another aspect of theinvention, the drive mechanism may comprise a pneumatically orhydraulically operated piston secured about one end of an elongate rod,with the retainer member being secured about the opposite end of theelongate rod for the displacement of annular sleeve along thelongitudinal axis of the composite tubing of the lamp when the piston isactivated.

[0015] In yet another aspect of the invention, the ultraviolet lightmodule may additionally comprise a housing for the drive mechanism,preferably configured so that the housing, ultraviolet light apparatus,and drive mechanism form a single unit. The housing, in turn, may alsoinclude a ballast for powering the ultraviolet light apparatus as wellas a socket means mounted to or integral with the housing for receivingthe ultraviolet lamp. A switch means may optionally be included with thehousing for automatically disconnecting electrical power to theultraviolet light-emitting lamp and/or drive mechanism when the housingis separated from the confined space, e.g., a conduit for the passage ofair therethrough to which the ultraviolet light module is incorporated.In addition, the housing may also include an electrically activated,audible and/or visual alarm when the ultraviolet light-emitting lamp,ballast or drive mechanism ceases to function.

[0016] As an ultraviolet light air treatment system, the housing,ultraviolet light apparatus and drive mechanism are configured to form asingle unit for incorporation with a conduit for treating the airpassing therethrough.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] A complete understanding of the present invention may be obtainedby reference to the following specification when taken in conjunctionwith the accompanying drawings wherein certain preferred embodiments areillustrated and wherein like numerals refer to like parts throughout.

[0018]FIG. 1 is an elevated plan view of an ultraviolet light airpurification system in accordance with the present invention.

[0019]FIG. 2 is an isolated top plan view of an exploded sleeve retainermember 58 for mounting with the annular sleeve 46 illustrated in FIG. 1.

[0020]FIG. 3 is an isolated top plan view of another embodiment of asleeve retainer member 64 for connection with the annular sleeve 46illustrated in FIG. 1.

[0021]FIG. 4 is a top plan view of the UV lamp 20 taken along line A-Aof FIG. 1, showing another embodiment for the assembly of sleeveretainer member 58 with annular sleeve 46 and a support arm stabilizermember 74.

[0022]FIG. 5 is an elevated plan view of the ultraviolet light airpurification system illustrated in FIG. 1 showing another embodiment forthe drive mechanism 48 in accordance with the invention.

[0023]FIG. 6 is an elevated plan view of the ultraviolet light airpurification system illustrated in FIG. 1 showing yet another embodimentfor the drive mechanism 48 in accordance with the invention.

[0024]FIG. 7 is a schematic diagram illustrating the electricalconnection between the UV lamp socket 22 and interlock switch 94,illustrated in FIG. 1, with ballast 90.

[0025]FIG. 8 is an elevated plan view of an another embodiment of theultraviolet light air purification system illustrated in FIG. 1.

[0026]FIG. 9 is an elevated plan view of yet another embodiment of theultraviolet light air purification system illustrated in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION AND BEST MODES THEREOF

[0027] An understanding of the present invention may be obtained byreference to the following description when taken in conjunction withthe accompanying drawings wherein certain preferred embodiments areillustrated and wherein like numerals refer to like parts throughout.

[0028] Referring to FIG. 1, a UV light air purification system 10 isillustrated which includes an air duct 12 having a generally rectangularcross-section defined in part by sidewalls 13 and 14 for the passage ofair therethrough. A duct opening 15 is provided in sidewall 13 for theincorporation of an ultraviolet light module 16 for the treatment of airwithin air duct 12. In the illustrations shown in FIGS. 1, 5 and 6,module 16 comprises a rectangularly shaped housing 24 having a hollowinterior defined by sidewalls 26 and 27, top wall 28 and platform 30.Platform 30 extends beyond sidewalls 26 and 27 of housing 24 in alateral direction parallel to sidewall 13 of air duct 12 to formrespective flanges 32 and 34 for the insertion of threaded screws 36, orsimilar fasteners, therethrough into duct sidewall 13. This has theeffect of securing housing 24, and hence module 16, to air duct 12.

[0029] As shown in FIG. 1, a lamp socket 22 is secured to the undersideof platform 30 of housing 24 to receive electrical pins 18 of at leastone UV lamp 20. When coupled with socket 22, UV lamp 20 will extend fromplatform 30 in a substantially perpendicular direction. As a result, UVlamp 20 will be disposed transversely to the flow of air in air duct 12when the lamp is inserted through duct opening 15 and the housing 24secured to duct wall 13. In the illustrations shown in FIGS. 1 and 5, UVlamp 20 has two pins, although more than two are contemplated dependingon the configuration of the UV lamp used, e.g., four-pin lamps 20illustrated in FIGS. 6 and 8. In FIGS. 1, 5, 6, and 8, UV lamp 20 isconfigured in a U-shaped arrangement whereby both ends of U-shaped tube21 are mounted to a lamp base such as end cap 19. Tube 21, however, neednot be restricted to a U-shaped configuration, and according to theinvention, may be configured as a straight length of tubing (see FIG. 9)or any other shape adapted for insertion into a conduit containing thepassage of air therethrough. For example, UV lamp 20 can be configuredas two parallel sections of tubing connected to each other about the endopposite to its common base, by a cross-section of tubing such as thatillustrated in FIG. 3 of U.S. Pat. No. 5,902,552.

[0030] The electrical pins 18 provided in end cap 19 are inserted into alamp socket 22 mounted to or integral with platform 30, which in turn iselectrically connected to a ballast 90 located within housing 24 forsupplying electrical power to UV lamp 20 (see also FIG. 7). It will beunderstood that the electrical ballast can be omitted from housing 24 ofmodule 16 when it is convenient or desirable to locate the ballast(s) ina remote location, e.g., with a source of electrical power forelectrically activating module 16.

[0031] With regard to the UV lamp 20 shown in FIG. 1, one of thestraight portions of U-shaped tube 21 has two sections of glass tubing,tubing 42 and tubing 44, joined together end-to-end to form a composite.The composite tubing has a cylindrical shape to provide a continuouslamp structure. Tubing 42, which is the shorter length illustrated inFIGS. 1, 5 and 6, is of the type that permits transmission ofultraviolet radiation within the UVC range of light as defined herein,and necessarily includes the wavelength for maximum ozone output ofabout 185 nanometers and the wavelength that generates maximumgermicidal activity at about 253.7 nanometers. Tubing 42, therefore,allows the transmission of ultraviolet light at radiation wavelengthsthat will generate a maximum amount of ozone when exposed to the air,and also at wavelengths for maximum germicidal activity. Tubing 42 isgenerally constructed of high quality clear quartz, typically known asVH-quartz which is available from the General Electric Company under theproduct designation GE Quartz, Type 214, or from the PhillipsCorporation under the product designation PH300/308. The GE Quartz, Type214 VH-quartz tubing will transmit UVC light at wavelengths in the 15 to280 nanometer range.

[0032] In the embodiments illustrated in FIGS. 1, 5 and 6, tubing 44 hasa longer length and extends to and includes the opposite parallelportion of U-shaped tube 21. Tubing 44 is also of the type that willpermit radiation of ultraviolet light within the UVC range but willblock the transmission of deep, high energy wavelengths that cause ozonegeneration, e.g., wavelengths below about 200 nanometers. Tubing 44 willtherefore allow the generation of ultraviolet light at wavelengths thatpermit germicidal activity, including maximum germicidal activity atabout 253.7 nanometers, while simultaneously blocking the transmissionof ultraviolet light necessary for the production of ozone, inclusive ofthe radiation wavelength of 185 nm. This type of glass or fused quartzis commonly referred to in the industry as L-quartz (which is quartzdoped with titanium dioxide) and is available from the General ElectricCompany under the product designation GE Quartz, Type 219, or from thePhillips Corporation under the product designation PH304.

[0033] The ozone output of UV lamp 20 may be varied and thereforecontrolled by the generally coaxial movement of an annular sleeve 46mounted in a frictionless manner about the partial length of thecomposite tubing formed by tubings 42 and 44. Annular sleeve 46 is sizedto permit its annular opening to be coaxially disposed about tubings 42and 44 so that the sleeve can be moved along the axial length of thecomposite tubing in a frictionless manner. It will be understood that inthe lamp configurations illustrated in FIGS. 1, 5 and 6, UV lamp 20 isprefabricated with annular sleeve 46 mounted in place. Annular sleeve 46is made of a transparent substance that is capable of blocking the UVwavelength of light for producing ozone while simultaneously permittingthe transmission of ultraviolet wavelength of light for generatinggermicidal activity, including maximum germicidal activity at awavelength of about 253.7 nanometers. It will be appreciated that thefused quartz or transparent Teflon® described below for annular sleeve46 will not entirely block the ultraviolet radiation wavelength thatgenerates ozone, e.g., as will a metal tube, but will block a verysubstantial portion of the ultraviolet radiation that generates ozone.Thus, only a very minor and insignificant amount of ozone may begenerated when sleeve 46 totally surrounds tubing 42. Accordingly, theterm “block” or “blocking” as used herein is meant to describe theability to substantially impede the transmission of ultraviolet light ina range that produces ozone.

[0034] Annular sleeve 46, which in FIGS. 1, 5 and 6 has a length equalto or greater than tubing 42, may be constructed of fused quartz, suchas L-quartz, or transparent Teflon®. The length of annular sleeve 46 issuch that it will substantially surround tubing 42 to block thetransmission of ozone to the degree desired. If maximum blockage isdesired, then the length of annular sleeve 46 will equal to or greater,is preferably greater, than that portion of tubing 42 which generatesthe transmission of ozone.

[0035] By utilizing a transparent annular sleeve with the foregoingqualifications and attributes, as opposed to a sleeve constructed of anon-transparent substance, e.g., a material such as that described inU.S. Pat. No. 5,751,007 which utilizes metal which entirely blocks allultraviolet light, or a transparent substance that absorbs thetransmission of ultraviolet light such as polycarbonate, a moreefficient UV light apparatus, module and air purification system isprovided. For example, when annular sleeve 46 partially or fully coverstubing 42 of UV lamp 20, UV light is still transmitted through tubing 42and annular sleeve 46 which includes the wavelength having maximumgermicidal activity, thereby offering a greater exposure of UV light tothe air passing through air duct 12.

[0036] In accordance with the invention, the UV light air purificationsystem and module also includes a drive mechanism 48 operablycommunicating with annular sleeve 46 for the upward and downwarddisplacement of the sleeve along the longitudinal axis of compositetubings 42 and 44 for varying the ozone output of UV lamp 20. Thisarrangement, which is illustrated in FIGS. 1,5 and 6, avoids mounting ofthe sleeve directly to the lamp tubing as undertaken in the disclosureof U.S. Pat. No. 5,751,007.

[0037] Referring to FIG. 1, one embodiment for the drive mechanism 48includes an elongate threaded rod 50 having a threadless end portion 51operatively engaged with an electric motor 54 located within housing 24for turning threaded rod 50 in a clockwise and counter-clockwise manner.As shown in greater detail in FIG. 2, threaded rod 50 is engaged with acorrespondingly threaded opening 56 provided within sleeve retainer 58.A correspondingly threaded nut 57 overlies threaded opening 56 and isfixed to sleeve retainer 58 to accommodate the receipt and properalignment of threaded rod 50 with the sleeve retainer. The oppositelower end 52 of rod 50 is threadless to limit the downward displacementof annular sleeve 46 relative to tubings 42 and 44. The end of sleeveretainer 58 opposite to its threaded opening 56 is provided with acircular opening 60 configured for receiving and retaining sleeve 46therein by any conventional means, for example, by a resistance fitthrough the employment of a resilient annular ring, e.g., an O-ring (notshown), secured about the circumference of opening 60.

[0038]FIG. 2 illustrates another embodiment of sleeve retainer 58according to the invention. The opposite, lateral portion of sleeveretainer 58 is configured in a semicircular fashion for engagingapproximately one half of the circumference of annular sleeve 46, theremaining circumference of the sleeve being embraced by a semicircularresilient clip 62 for containing annular sleeve 46 within the circularopening 61 defined by the joinder of sleeve retainer 58 with resilientclip 62. A pair of respectively mateable notches 63,65 and 64,66 isprovided about the respective ends of sleeve retainer 58 and resilientclip 62 for securing annular sleeve 46 to sleeve retainer 58.

[0039] Yet another arrangement for fixing annular sleeve 46 to sleeveretainer 58 is illustrated in FIG. 3 wherein a circular portion of a“broom” clip 64 is secured about the end 66 of sleeve retainer 58, e.g.,by welding, opposite the threaded opening 56 for receiving threaded rod50. “Broom” clip 64 is resilient in makeup and has an opening 68 forsecurely receiving and retaining annular sleeve 46 therein. In thismanner, “broom” clip 64 can be pushed onto annular sleeve 46 to hold thesleeve firmly in place with sleeve retainer 58.

[0040] As shown in FIG. 4, an elongate guide rod 70, deployed through anopening 72 within a support arm stabilizer member 74 coupled with sleeveretainer 58 via threaded rod 50, may be optionally utilized to preventthe transfer of any torsional forces to annular sleeve 46 when threadedrod 50 is rotated within the threaded opening 56 of sleeve retainer 58.Guide rod 70 is secured to sidewalls 5 and 6 (not shown) by anyconventional means, and the opening 72 through which it passes is ofsufficient size to permit support arm stabilizer 74 to move freely alongthe length of guide rod 70.

[0041] The drive mechanism of module 16, according to the invention, mayalso be manually operated without the necessity of using electric motor54. For example, as shown in FIG. 5, at least one threaded nut 76 may bepositioned and fixed within (or without) housing 24, the nut axiallycoinciding with openings 78 and 79 to receive threaded rod 50therethrough. The lower end portion of rod 50 is threadless and coupledwith an open ended receptacle 80 retained within sleeve retainer 58. Theend portion of threaded rod 50 is configured to have a narrower diameterfor slidable engagement with receptacle 80 (not shown) to permit itsfree rotation within the receptacle. Receptacle 80 may be held in placeabout the narrowed end portion of rod 50 by any conventional means, suchas, for example, by the employment of a retainer clip or snap ring. Thetop portion of threaded rod 50 is provided with a handle 82 for manuallyturning the rod in a clockwise or counter-clockwise fashion to adjustthe positioning of annular sleeve 46 about tubing 42. In this manner,the amount of ozone emitted from UV lamp 20 can be adjusted according tothe needs demanded by the ambient surroundings within air duct 12 andthe environment to which the air is being conducted.

[0042] As an alternative to the use of threaded rod 50 for the upwardand downward displacement of annular sleeve 46, the movement of annularsleeve 46 along the axial length of tubing 42 may be accomplished by apneumatically or hydraulically operated piston and rod combination.Referring to FIG. 6, a piston 84, whose pneumatic or hydraulic operationis conventionally known, is vertically disposed within housing 24 withthe top portion thereof projecting through opening 86 provided in topwall 28. Extension rod 88 is fixed with and depends from piston 84, theopposite end of which is coupled with sleeve retainer 58 in much thesame manner illustrated in FIG. 5. The lower end portion of extensionrod 88 is threadless and coupled with an open ended receptacle 80retained within sleeve retainer 58. The end portion of extension rod 88is configured to have a narrower diameter for slidable engagement withreceptacle 80 (not shown). Receptacle 80 may be held in place about thenarrowed end portion of extension rod 88 by any conventional means, suchas, for example, by means of a retainer clip or snap ring. The advantageof using a piston/rod combination for the vertical displacement ofannular sleeve 46 in FIG. 6 is that any torsional forces that may beencountered by annular sleeve 46 through the use of threaded rod 50 inthe embodiment shown in FIG. 1, are avoided. It will be understood thatin accordance with the invention, any conventional drive mechanism meanscan be used to displace annular sleeve 46.

[0043] In order to facilitate the operation of module 16, housing 24will preferably incorporate the electronics schematically illustrated inFIG. 7. As shown in FIGS. 1 and 7, the operation of UV lamp 20 ispowered by ballast 90. Electrical motor 54, also retained within housing24, is electrically connected to circuit board 92 which in turn receivesits power from an electrical source preferably located exteriorly ofhousing 24 (not shown). When power is supplied to circuit board 92, andin turn to ballast 90, electric motor 54 and to an interlock switch 94(described below), tubing 42 of UV lamp 20 will produce ultravioletlight in a radiation wavelength range within the full UVC radiationspectrum, inclusive of the 185 nanometer (i.e., below 200 nanometers)and 254.3 nanometer wavelengths for generating maximum ozone andgermicidal output, respectively. Tubing 44 of UV lamp 20 will transmitUV light in a radiation wavelength range that produces germicidalactivity, inclusive of the 254.3 nanometer wavelength. When it isdesired to attenuate or reduce the amount of ozone being produced bymodule 16, electric motor 54 will be activated by an appropriate switch(not shown) operably connected to circuit board 92, to rotate threadedrod 50 in a clockwise direction. Annular sleeve 46, which is constructedof L-quartz or Teflon®, will then be displaced in the upward directionto partially cover tubing 42, thereby blocking a proportionate amount ofozone producing ultraviolet light, and hence the amount of ozone,emitted from UV lamp 20. As electrical motor 54 continues to rotate in aclockwise fashion, annular sleeve 46 will continue in the upwarddirection until tubing 42 is completely enveloped, thereby blocking theradiation wavelength of UV light for producing ozone. It will be noted,however, that the UV light wavelengths above those for producing ozone(generally above 200 nm), including the 253.7 nanometer wavelength formaximum germicidal activity, will continue to pass through annularsleeve 46. This has the net effect of not decreasing the amount ofgermicidal activity generated by UV lamp 20 even though the lamp is nolonger producing ozone.

[0044] In similar fashion, when electrical motor 54 reverses therotation of threaded rod 12 in a counter clockwise direction, annularsleeve 46 will move in a downward direction to expose tubing 42 andthereby allow controlling amounts of ozone to be introduced into airduct 12 by module 16. By displacing annular sleeve 46 in a manner toexpose more or less of tubing 42, the amount of ozone produced by module16 can be controlled from a location remote from the interior of airduct 12. Moreover, by moving annular sleeve 46 over the lower radiationwavelength tubing 42, the amount of lower radiation wavelength UV lighttransmitted for the production of ozone can be either blocked orattenuated without affecting the transmission of the higher radiationwavelength UV light emitted from the lower and higher radiationwavelength tubing 44. Not only is the lamp's germicidal activityincreased, the ozone levels produced by the lamp can be controlledwithout disassembly of the duct, shutting down the system, or movementor replacement of UV lamp 20.

[0045] The ultraviolet light apparatus of the invention includes otherembodiments, for example, that which is illustrated in FIGS. 8 and 9.Referring to FIG. 8, in place of the composite tubing formed by tubings42 and 44 in the embodiments illustrated in FIGS. 1, 5 and 6, the entireU-shaped tube 21 of UV lamp 20 may be configured of pure quartz, e.g.,VH-quartz, that permits the transmission of ultraviolet light within theUVC range for the generation of both ozone and germicidal activity,inclusive of the 185 and 253.7 nanometer wavelengths. In thiscircumstance, annular sleeve 46 a in FIG. 8 will be of a length andconfiguration to completely surround U-shaped tube 21. Therefore, whenit is desired to treat the air flowing through air duct 12 withoutozone, annular sleeve 46 a will be movably displaced about U-shaped tube21 to prevent or control the generation of ozone while still allowingthe transmission of ultraviolet light to the air in air duct 12 forgenerating germicidal activity. The displacement of annular sleeve 46 aalong the length of U-shaped tube 21 utilizing any of the drivemechanisms described hereinbefore, enables the production of ozone to beblocked or controlled. The advantage of this aspect of the invention isthat the need for composite tubing in the UV lamp is dispensed with.

[0046] It will be understood that while annular sleeve 46 describes acylindrical configuration in FIGS. 1, 5, 6 and 9, sleeve 46 a in FIG. 8has a configuration whose opening is slightly larger than andapproximates the cross-sectional area of U-shaped tube 21. It will alsobe understood that while it is preferred that the opening within annularsleeve 46 a be slightly larger than the cross-sectional area of thetubing or lamp which it surrounds, it does not exclude other geometricconstructs that will promote and economize the efficient control ofozone production from a corresponding UV lamp. In addition, providedthat a greater degree of control for the generation of ozone is desired,annular sleeve 46 a may be closed at the bottom thereof (not shown) toprovide a “test tube” type configuration for the sleeve in order toprevent the generation of ozone from the rounded bottom portion 21 a ofU-shaped tubing 21.

[0047] In place of U-shaped tubing 21 illustrated in FIG. 8, the tubingof UV lamp 20 may have a straight cylindrical length as designated bythe reference numeral 23 in FIG. 9. As with the U-shaped tubing 21 shownin FIG. 8, straight tubing 23 of UV lamp 20 a is constructed of purequartz, e.g., VH-quartz, that permits the transmission of ultravioletlight within the UVC range for the generation of both ozone andgermicidal activity, inclusive of the 185 and 253.7 nanometerwavelengths. UV lamp 20 a is provided with end caps 19 a, 19 b mountedat the respective ends of tubing 23 for receiving electrical wires (notshown) from their respective filaments. As is well known in the art, theelectrical wires which lead from the bottom lamp filament and emanatefrom end cap 19 b (not shown) are extended along the outside of tubing23 for ultimate connection to ballast 90 within housing 24, generallyvia an extra pair of electrical pins provided in end cap 19 a whichwould render UV lamp 20 a a four-pin lamp. At the opposite end of tubing23, end cap 19 a is provided with a pair of electrical pins 18 to makeelectrical contact with corresponding lamp socket 22 which in turn ismounted to or integral with platform 30 of housing 24. Thus, when theend cap 19 of UV lamp 20 is plugged into lamp socket 22, the lamp willextend from platform 30 into the interior of air duct 12 as housing 24is secured to the sidewall 13 of the air duct with threaded screws 36.

[0048] Annular sleeve 46 b is of a cylindrical length to completelysurround tubing 23 in a frictionless manner. Like sleeve 46 in FIGS. 1,5 and 6 and sleeve 46 a in FIG. 8, annular sleeve 46 b is such that itis capable of blocking ultraviolet light in a wavelength range thatproduces ozone while simultaneously allowing the transmission ofultraviolet light in a wavelength range that produces germicidalactivity. Annular sleeve 46 b, as well as sleeve 46 a, is preferablyconstructed of L-quartz or transparent Teflon®.

[0049] When it is desired to generate maximum ozone output from UV lamp20 a, annular sleeve 46 b in FIG. 9 will be downwardly displaced to thefullest extent allowed by threaded rod 50 of drive mechanism 48 to fullyexpose the length of straight tubing 23 that transmits ultraviolet lightwithin the UVC range. In order to prevent or control the generation ofozone, drive mechanism 48 is activated to displace annular sleeve 46 inthe upward direction for fully or partially covering straight tubing 23.

[0050] The UV air disinfection system according to the invention mayemploy optional devices to facilitate the functioning of the system. Forexample, FIGS. 1, 8 and 9 show an interlock switch 94 secured withinhousing 24 for automatically disconnecting power to the ultraviolet lampwhen housing 24 is removed or lifted from side wall 13 of air duct 12.The interlock switch (which may also be disposed outside of housing 24)includes a spring biased push button 96 extending through an opening 98provided in platform 30. When housing 24 is placed over opening 15 inside wall 13 for insertion of UV lamp 20 into duct 12, push button 96will be depressed as it comes into contact with and rests upon side wall5, and through appropriate wiring to circuit board 92 illustrated inFIG. 7, the power to UV lamp 20 will be automatically turned on. Theautomatic disconnection of power to UV lamp 20 when module 16 is removedfrom air duct 12 will prevent inadvertent exposure to the harmfuleffects of the ultraviolet light emanating from UV lamp 20.

[0051] In addition to the interlock switch 94, the UV light airpurification system 10 may also include an ozone detection apparatuscomprising an ozone level sensor (not shown) inserted into the airpassageway of duct 12 for monitoring the ozone levels produced by UVlamp 20. The ozone level sensor, which is interfaced with circuit board92, will provide adequate notice of high levels of ozone byelectronically activating a visual alarm, such as the LED indicatorlight 102 shown in FIG. 7. The ozone detection apparatus may also beused to automatically adjust the ozone output to preset levels byprogramming a microprocessor interfaced with circuit board 92 withinstructions for activating electric motor 54 or piston 84 to adjustannular sleeve 46 according to the preset levels of ozone output.

[0052] The UV air purification system may also include an electricallyoperated audible alarm 104 and/or visual alarm, such as the LEDindicator light 102 shown in FIG. 7, incorporated with (or as an adjunctto) circuit board 92 for activation in the event UV lamp 20 or the drivemechanism malfunctions, e.g., if the lamp burns out or short circuits,or if electric motor 54 or piston 84 ceases to provide movement toannular sleeve 46.

[0053] The system, module, apparatus and methods according to theinvention herein provide an inexpensive and economical means by whichthe production of ozone within a confined structure, such as a HVACduct, can be remotely controlled without disturbing other systemcomponents and apparatus, and without affecting and/or impeding thegermicidal activity of the UV lamp.

What is claimed is:
 1. An ultraviolet light module for the treatment ofair within a confined space comprising: (a) an ultraviolet lightapparatus comprising an ultraviolet light-emitting lamp that includes atleast one composite tubing, said composite tubing comprising: (i) afirst section for transmitting ultraviolet light in a wavelength rangethat includes maximum ozone production and maximum germicidal activity,and (ii) a second section for transmitting ultraviolet light in awavelength range that includes maximum germicidal activity and excludesthe production of ozone; and (iii) an annular sleeve, the annulus ofsaid sleeve (A) completely surrounding a portion of the composite tubingof said lamp; and (B) being capable of blocking ultraviolet light in awavelength range that produces ozone while simultaneously allowing thetransmission of ultraviolet light in a wavelength range that producesgermicidal activity; and (b) a drive mechanism for the frictionlessdisplacement of said annular sleeve along the longitudinal axis of saidcomposite tubing for controlling the amount of ozone transmitted by saidultraviolet light apparatus.
 2. The module according to claim 1 whereinsaid lamp comprises two, substantially parallel, tubularly connectedsegments, the first section of said composite tubing forming a portionof at least one of said segments.
 3. The module according to claim 1wherein said sleeve allows the transmission of ultraviolet light that isinclusive of the wavelength range for producing maximum germicidalactivity.
 4. The module according to claim 1 wherein said sleeve has acylindrical configuration and is of sufficient length to completelysurround the first section of the composite tubing of said lamp.
 5. Themodule according to claim 1 wherein said sleeve is constructed of fusedquartz.
 6. The module according to claim 1 wherein said sleeve isconstructed of transparent Teflon.
 7. The module according to claim 1wherein said drive mechanism comprises an elongate threaded rod engagedat one end portion thereof with a means for rotating said rod, theopposite end portion of said rod being operatively engaged with acorrespondingly threaded opening within a retainer member fixed to saidsleeve for displacing said sleeve along the longitudinal axis of thecomposite tubing of said lamp when said rod is rotated.
 8. The moduleaccording to claim 7 wherein said means for rotating said rod comprisesan electric motor.
 9. The module according to claim 7 wherein said meansfor rotating said rod comprises a handle for the manual rotation of saidrod.
 10. The module according to claim 1 wherein the drive mechanismcomprises a pneumatically or hydraulically operated piston secured aboutone end of an elongate rod, said retainer member being secured about theopposite end of said elongate rod for the displacement of said sleevealong the longitudinal axis of the composite tubing of said lamp whensaid piston is activated.
 11. The module according to claim 1additionally comprising a housing for said drive mechanism.
 12. Themodule according to claim 11 wherein said housing, ultraviolet lightapparatus, and drive mechanism form a single unit.
 13. The moduleaccording to claim 12 wherein said housing additionally includes aballast for powering said ultraviolet light apparatus.
 14. The moduleaccording to claim 13 wherein said housing additionally includes aswitch means for automatically disconnecting power to said lamp whensaid housing is separated from said confined space.
 15. The moduleaccording to claim 13 wherein said housing additionally includes anelectrically activated, audible and/or visual alarm when said lamp,ballast or drive mechanism ceases to function.
 16. An ultraviolet lightapparatus for the treatment of air comprising an ultravioletlight-emitting lamp that includes at least one composite tubing, saidcomposite tubing comprising: (a) a first section for transmittingultraviolet light in a wavelength range that includes maximum ozoneproduction and maximum germicidal activity; and (b) a second section fortransmitting ultraviolet light in a wavelength range that includesmaximum germicidal activity and excludes the production of ozone; and(c) a movable annular sleeve, the annulus of said sleeve (i) beingcapable of completely surrounding a portion of the composite tubing ofsaid lamp in a frictionless manner; and (ii) being capable of blockingultraviolet light in a wavelength range that produces ozone whilesimultaneously allowing the transmission of ultraviolet light in awavelength range that produces germicidal activity.
 17. The apparatusaccording to claim 16 wherein said lamp comprises two, substantiallyparallel, tubularly connected segments, the first section of saidcomposite tubing forming a portion of at least one of said segments. 18.The apparatus according to claim 16 wherein said sleeve allows thetransmission of ultraviolet light that is inclusive of the wavelengthrange for producing maximum germicidal activity.
 19. The apparatusaccording to claim 16 wherein said sleeve has a cylindricalconfiguration and is of sufficient length to completely surround thefirst section of the composite tubing of said lamp.
 20. The apparatusaccording to claim 16 wherein said sleeve is constructed of fusedquartz.
 21. The apparatus according to claim 16 wherein said sleeve isconstructed of transparent Teflon.
 22. An ultraviolet light system forthe treatment of air comprising: (a) a conduit for the passage of airtherethrough; (b) an ultraviolet light apparatus comprising anultraviolet light-emitting lamp that includes at least one compositetubing, said composite tubing comprising: (i) a first section fortransmitting ultraviolet light in a wavelength range that includesmaximum ozone production and maximum germicidal activity; (ii) a secondsection for transmitting ultraviolet light in a wavelength range thatincludes maximum germicidal activity and excludes the production ofozone; and (iii) an annular sleeve, the annulus of said sleeve (A) beingcapable of completely surrounding a portion of the composite tubing ofsaid lamp; and (B) being capable of blocking ultraviolet light in awavelength range that produces ozone while simultaneously allowing thetransmission of ultraviolet light in a wavelength range that producesgermicidal activity; (c) a drive mechanism for the frictionlessdisplacement of said annular sleeve along the longitudinal axis of saidcomposite tubing for controlling the amount of ozone transmitted by saidultraviolet light apparatus within said conduit; and (d) a housing forsaid drive mechanism, said housing, ultraviolet light apparatus anddrive mechanism forming a single unit that is incorporated with saidconduit.
 23. The system according to claim 22 wherein said lampcomprises two, substantially parallel, tubularly connected segments, thefirst section of said composite tubing forming a portion of at least oneof said segments.
 24. The system according to claim 22 wherein saidsleeve allows the transmission of ultraviolet light that is inclusive ofthe wavelength range for producing maximum germicidal activity.
 25. Thesystem according to claim 22 wherein said sleeve has a cylindricalconfiguration and is of sufficient length to completely surround thefirst section of the composite tubing of said lamp.
 26. The systemaccording to claim 24 wherein said sleeve is constructed of fusedquartz.
 27. The system according to claim 24 wherein said sleeve isconstructed of transparent Teflon.
 28. The system according to claim 22wherein said drive mechanism comprises an elongate threaded rod engagedat one end portion thereof with a means for rotating said rod, thethreaded portion of said rod being operatively engaged with acorrespondingly threaded opening within a retainer member fixed to saidsleeve for displacing said sleeve along the longitudinal axis of thecomposite tubing of said lamp when said rod is rotated.
 29. The systemaccording to claim 28 wherein said means for rotating said rod comprisesan electric motor.
 30. The system according to claim 28 wherein saidmeans for rotating said rod comprises a handle for the manual rotationof said elongate threaded rod.
 31. The system according to claim 28additionally comprising a guide rod detachably fixed to said conduit andcommunicating with a slidable stabilizer member fixed to said retainermember in parallel relationship with said threaded rod to prevent thetransmission of torsional forces to said sleeve by the rotation of saidthreaded rod.
 32. The system according to claim 22 wherein the drivemechanism comprises a pneumatically or hydraulically operated pistonsecured about one end of an elongate rod, said retainer member beingsecured to said elongate rod for the displacement of said sleeve alongthe longitudinal axis of the composite tubing of said lamp when saidpiston is activated.
 33. The system according to claim 22 wherein saidhousing additionally includes a ballast for powering said ultravioletlight apparatus.
 34. The system according to claim 33 wherein saidhousing additionally includes a switch means for automaticallydisconnecting power to said lamp when said housing is separated fromsaid conduit.
 35. The system according to claim 33 wherein said housingadditionally includes an electrically activated, audible and/or visualalarm when said lamp, ballast or drive mechanism ceases to function. 36.An ultraviolet light apparatus for the treatment of air comprising anultraviolet light-emitting lamp whose tubing transmits ultraviolet lightin a wavelength range that includes maximum ozone production and maximumgermicidal activity; and a movable annular sleeve, the annulus of saidsleeve (i) being capable of completely surrounding the tubing of saidlamp in a frictionless manner; and (ii) being capable of blockingultraviolet light in a wavelength range that produces ozone whilesimultaneously allowing the transmission of ultraviolet light in awavelength range that produces germicidal activity.